Sketchbooks are among my favorite things. Keeping one makes me happy, and seeing that other people keep them almost even happier. I also love going to new places, so when I ran across this (rather popular) blog, it was a dream come true.
Urban Sketchers is a blog with many participants. The criteria? Life sketches, from all over the world. Scrolling through the entries is like taking an illustrated international journey. The drawings can vary from enormous cathedrals to an individual plate of food. The media is varied too–all kinds of paper with all kinds of ink, paint, and graphite.
It also has a Flickr group, which is easier to join than the actual blog (there's some kind of initiation process).
Oh yeah! For a little Paper Bicycle hometown pride , the Twin Cities has an Urban Sketchers spin-off blog!